UNIVERSITY    OF   CALIFORNIA 

COLLEGE    OF    AGRICULTURE 

AGRICULTURAL   EXPERIMENT  STATION 

CIRCULAR  No.  271 
October,  1923 

BROODING  CHICKS  ARTIFICIALLY 

BY 

J.  E.  DOUGHEBTY  and  S.  S.  GOSSMAN 


CONTENTS  pAGE 

Building  the  brooder  house 2 

Good  ventilation  without  drafts 2 

Sunlight 5 

Safety  from  fire 6 

Temperature  flexibility 6 

Ample  heat  capacity 7 

Economy  of  heating 9 

Dependable  heating  system  a  necessity 10 

Simplicity  and  durability  of  construction 12 

Ease  in  cleaning 12 

Convenience  of  operation 13 

Size  of  hover 13 

Scratching  space  outside  the  hover 14 

Toe  picking 14 

Size  of  the  pen 15 

System  of  yarding 16 

Summer  shade 19 

Feeding  young  chicks 20 

First  care  of  chicks 20 

Feeding  milk 21 

Milk  treatment  for  coccidiosis 21 

Feeding  grain 22 

Changing  from  chick  to  growing  grains 24 

Feeding  mash 24 

Green  feed 25 

Crowding 26 

Separation  of  sexes 26 

Chicks  piling  up 26 

Teaching  chicks  to  roost 27 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


BUILDING  THE  BKOODER  HOUSE 
A  brooder  house  designed  to  brood  chicks  or  turkey  poults  arti- 
ficially, should  fulfill  certain  requirements  if  satisfactory  results  are 
to  be  obtained.  These  requirements  should  not  make  the  construction 
more  complicated  nor  add  to  the  cost,  but  should  facilitate  the  rearing 
of  strong,  thrifty  stock.  In  the  following  pages  these  essentials  are 
discussed  in  detail  and  the  construction  of  brooding  houses  that  will 
best  embody  them  under  California  conditions  is  described.  Since  the 
heating  system  is  an  inseparable  part  of  a  brooder  house,  and  is  often 
built  in,  it  must  be  considered  in  relation  to  the  design  of  the  house. 
Due  consideration  is  accordingly  given  to  this  problem. 


Fig.  1. — This  type  of  open  front  colony  house  makes  an  excellent  brooding 
and  rearing  house.  The  house  shown  is  8'  x  8'  in  size  and  of  knock-down  con- 
struction, but  it  may  be  built  wider  and  any  length  desired. 

Good  Ventilation  Without  Drafts. — Pure  fresh  air  is  even  more 
important  for  poultry  than  for  larger  farm  stock.  The  body  tempera- 
ture of  poultry  is  several  degrees  higher  than  that  of  other  farm 
animals;  their  digestive  system  functions  more  rapidly,  and  oxygen 
being  indispensable  to  the  assimilation  of  food,  the  respiration  must 
be  increased  to  meet  this  need.  It  is  therefore,  of  vital  importance 
that  the  system  of  ventilation  used  in  the  brooder  house  be  such  as 
will  rapidly  remove  the  stale,  vitiated  air,  charged  with  carbon  dioxide 
from  the  chicks'  lungs,  with  lamp  fumes  (if  a  blue  flame  coal-oil 
brooder  stove  is  used),  and  with  odors  from  the  droppings.  Close  con- 
finement in  poorly  ventilated  quarters  soon  saps  the  vitality  of  growing 
chicks,  retards  their  growth,  and  increases  the  death  rate.    Combined 


Circular  271 J  brooding  CHICKS  ARTIFICIALLY  3 

with  the  heavy  feeding  of  concentrated  rations,  such  conditions  are 
also  conducive  to  leg  weakness  and  other  ills. 

The  open  front  house  of  limited  height,  equipped  with  curtains, 
(fig.  1)  represents  one  of  the  simplest  systems  of  effective  ventilation. 
Another  method  which  is  desirable  for  larger  brooding  houses  is  the 
King  System.1  In  this  system,  fresh  air  is  taken  in  near  the  ceiling 
and  the  stale  air  is  withdrawn  through  ventilating  shutes  extending 
from  about  18"  above  the  floor  to  a  point  sufficiently  higher  than  the 
highest  part  of  the  roof  to  provide  effective  suction. 

Good  ventilation  of  the  brooder  house  itself  does  not  necessarily 
insure  a  sufficient  ventilation  of  the  hovers,  unless  these  are  so  con- 
structed as  to  permit  a  reasonably  free  circulation  of  air.  In  hovers 
equipped  with  muslin  or  canvas  curtains  which  hang  close  to  the  floor 
and  greatly  restrict  the  circulation  of  air,  sufficient  ventilation  is 
practically  impossible,  even  when  electric  or  hot  water  heat  is  used, 
neither  of  which  vitiates  the  air  as  does  an  oil  heater.  This  seems  to 
be  especially  true  with  a  type  of  electric  hover  tested  at  this  Station, 
which  depends  for  ventilation  on  the  natural  diffusion  of  air  in  and 
out  of  the  hover  through  the  curtains.  Electric  hovers  are  very  sensi- 
tive to  temperature  changes  and  exact  in  temperature  regulation. 
There  is  no  surplus  heat  given  off  to  stimulate  air  circulation  and 
cause  the  chicks  to  spread  out  toward  the  edges  of  the  hover  where  the 
air  is  fresher ;  or  even  to  sleep  with  their  heads  sticking  through  the 
curtain  slits  into  the  cool  outer  air  of  the  room  and  their  bodies  inside 
and  warm,  as  commonly  occurs  with  hovers  heated  by  oil  or  water. 

In  electric  hovers  of  this  type  the  beat  from  the  bodies  of  the  chicks 
added  to  that  from  the  coils,  soon  heats  the  hover  to  the  point  where 
the  thermostat  cuts  off  the  current.  There  is  no  surplus  heat  to  cause 
the  chicks  to  spread  out  toward  the  outside  and  they  remain  well  inside 
the  hover  where  the  accurate  regulation  keeps  the  temperature  just 
comfortable.  As  a  result,  they  may  not  get  enough  fresh  air  and  their 
vigor  is  impaired. 

In  such  brooders,  moreover,  the  moisture  thrown  off  with  the  air 
exhaled  by  the  chicks  is  not  carried  away,  but  adds  to  the  humidity 
of  the  air  in  the  hover.  This  humidity  may  increase  to  a  point  where 
moisture  is  precipitated  and  the  chicks  arc  said  to  "  sweat/ '  The 
droppings  do  not  dry  out  but  remain  moist  and  are  tramped  into  and 
absorbed  by  the  litter,  forming  a  damp,  foul-smelling  mat  of  manure 
and  straw  which  must  be  cleaned  out  every  day  if  the  hover  is  run  at 
full  capacity. 

i  Originated  by  Professor  F.  H.  King  of  the  University  of  Wisconsin  and 
described  in  his  book,  "Ventilation  for  Dwellings,  Rural  Schools  and  Stables." 
Mrs.  F.  H.  King,  Publisher,  Madison,  Wisconsin. 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


Unless  a  hover  has  a  positive  system  of  fresh  air  ventilation,  it 
should  not  sit  so  close  to  the  floor  as  to  restrict  a  free  circulation  of 
air  beneath.  Curtains,  if  used,  should  hang  at  least  one  or  two  inches 
above  the  floor  at  first  and  be  gradually  raised  higher  as  the  chicks 
become  older  and  stronger.  With  oil  and  gas  brooder  stoves  which 
discharge  the  products  of  combustion  directly  into  the  air  of  the  hover, 
the  lower  edge  of  the  galvanized  iron  canopy  should  be  not  less  than 
four  inches  above  the  floor  and  curtains  should  not  be  used. 


Fig.  2. — Hot  water  brooding  system  in  which  the  hovers  B  are  heated  and 
ventilated  by  heated  air  drawn  from  the  walkway  C.  The  passage  of  the  air 
into  the  adjustable  opening  controlled  by  door  A,  up  through  the  chamber 
heated  by  the  hot  water  pipes  and  into  the  hover  B  is  indicated  by  arrows. 

Poultry  keepers  are  realizing  more  and  more  the  value  of  effective 
ventilation  in  promoting  the  rapid,  hardy  growth  of  chicks  and 
greater  numbers  of  brooding  systems  which  combine  with  the  heat 
supply  a  positive  method  of  ventilation  of  the  hover  are  being  installed 
each  year.  Figure  2  illustrates  a  hot  water  system  using  this  method 
of  fresh  air  heating.  Fresh  heated  air  is  discharged  directly  into  the 
hovers  through  intake  openings  with  manually  operated  doors  which 
control  the  amount  of  fresh  warm  air  entering  each  hover.  This 
arrangement  also  permits  a  maximum  of  flexibility  in  temperature 
regulation  under  the  hover,  because  the  volume  of  fresh  heated  air 
entering  any  hover  can  be  controlled.  For  chicks  less  than  a  week  old 
the  shutters  may  be  kept  wide  open.  They  can  then  be  closed  grad- 
ually from  week  to  week,  according  to  the  coldness  of  the  weather. 
Chicks  require  less  heat  and  spend  less  time  under  the  hover,  even 
at  night,  as  they  grow  larger  and  stronger. 


Circular  271] 


BROODING    CHICKS    ARTIFICIALLY 


In  the  case  of  electric  and  oil  heated  hovers,  the  fresh  air  can  be 
introduced  through  ducts  or  a  false  floor  with  fresh  air  intakes  (fig.  3). 
The  fresh  air  is  then  carried  into  the  hover  through  a  galvanized 
iron  tube  about  four  inches  in  diameter  located  in  the  center  of  the 
hover  and  extending  from  the  floor  to  within  a  few  inches  of  the  top. 
The  heating  coils  may  be  located  in  the  false  floor  to  heat  the  air 
before  it  enters  the  hover  or  may  be  placed  in  the  top  of  the  hover  to 
heat  the  air  as  it  is  discharged  into  these  heating  coils. 


Fig.  3. — Electric  hover  with  positive  system  of  ventilation.     Arrows  show 
how  fresh  air  enters  under  the  false  floor  and  passes  into  the  hover. 


Brooder  houses  with  walkways  and  wire  mesh  partitions  are  very 
apt  to  be  drafty.  The  opening  of  windows  in  the  walk-way  while 
chick  exits  on  the  opposite  side  of  the  house  are  open,  may  set  up 
strong  air  currents  along  the  floor  of  a  brooder  pen  and  chill  the 
chicks.  Floor  drafts  being  very  detrimental,  the  location  and  con- 
struction of  all  openings,  such  as  chick  doors,  and  ventilating  windows, 
should  be  carefully  considered  in  erecting  a  brooder  house. 

Sunlight. — Sunlight  instills  warmth  and  cheer  into  the  atmosphere 
in  cool  weather;  it  increases  the  illumination  within  a  brooder  house; 
it  is  Nature's  most  effective  destroyer  of  germs.  Intense  sunlight 
should  not  strike  directly  on  the  floor  of  a  brooding  pen,  however. 


b  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

because  young  chicks  have  a  tendency  to  bask  in  warm  patches  of 
sunshine  and  become  inactive  and  sleepy  instead  of  keeping  active 
and  busy.  An  adjustment  of  the  curtains  or  an  application  of  Sapolio 
or  Bon  Ami  on  the  window  glass  through  which  direct  sunlight  strikes 
the  floor,  will  prevent  these  conditions. 

Safety  From  Fire. — Fire  risk  should  not  be  overlooked  in  pur- 
chasing and  installing  brooder  heating  devices.  In  constructing  home- 
made brooders,  especially,  the  fire  risk  involved  is  not  always  properly 
appreciated  and  taken  care  of.    As  a  result,  costly  fires  occur  annually. 


Fig-.  4. — Two  views  of  hovers  heated  by  overhead  hot  water  pipes.  Increased 
ventilation  is  obtained  with  style  of  hover  shown  by  first  removing  the  front, 
and  later  the  rear,  burlap  curtains.  Boosts  are  placed  on  top  of  hover  when 
the  chicks  are  being  taught  to  roost. 

Perhaps  one  of  the  greatest  advantages  that  can  be  urged  in  favor 
of  the  hot  water  system  of  heating  is  its  very  great  safety  from  fire, 
provided  the  heater  is  installed  with  due  care.  With  this  system  there 
is  only  one  fire  and  it  can  be  readily  enclosed  in  a  fireproof  compart- 
ment. With  hovers  using  open  flame  oil  burners,  on  the  other  hand, 
the  fire  risk  is  much  greater.  If  the  burners  are  intelligently  handled 
and  kept  clean  the  fire  risk  is  comparatively  small,  but  such  burners 
must  not  be  neglected.  Ample  precaution  against  fire  is  the  cheapest 
possible  fire  insurance. 

Temperature  Flexibility. — Temperature  flexibility  refers  to  regu- 
lation of  temperature  of  any  given  hover  independently  of  any  other 
hover.  Chicks  need  less  and  less  artificial  heat  as  they  grow  larger 
and  stronger.  Keducing  the  hover  temperature  rapidly,  without  mak- 
ing the  chicks  uncomfortable,  stimulates  strong,  quick  growth.  Too 
high  temperatures  tend  to  reduce  the  vitality  of  growing  stock  and 
develop  ' '  hot-house  chicks. ' ' 

One  of  the  most  serious  defects  of  the  "overhead"  hot  water  pipe 
system  (fig.  4)  in  which  pipes  extend  through  the  hovers  above  the 


Circular  271]  brooding   CHICKS  ARTIFICIALLY  7 

chicks,  is  the  impossibility  of  regulating  the  temperature  of  each  hover 
independently  to  meet  the  needs  of  chicks  of  different  ages.  Since  all 
of  the  hovers  are  heated  by  the  same  flow  and  return  pipes,  the  tem- 
perature in  each  hover  is  the  same  as  far  as  the  heat  radiated  by  the 
hot  water  pipes  is  concerned.  It  is  only  by  means  of  some  expedient 
such  as  removing  the  side  curtains  or  raising  the  hovers  higher  from 
the  floor  to  increase  ventilation,  that  the  temperature  in  any  given 
hover  can  be  decreased  as  the  chicks  grow  older.  A  hot  water  system 
of  this  type  has  the  advantage,  however,  of  being  the  simplest  and 
the  least  expensive  heating  device  that  can  be  installed  in  a  permanent 
brooder  house.  If  the  design  of  the  hovers  is  such  that  the  tempera- 
ture can  be  effectively  regulated  by  increasing  or  decreasing  the 
ventilation,  excellent  results  will  be  obtained. 

To  overcome  the  failure  of  the  ' '  overhead ' '  pipe  system  to  govern 
the  temperature  of  each  hover  independently  by  regulating  the  heat 
supplied  to  it,  other  hot  water  heating  pipe  systems  have  been  devised. 
In  these  later  systems  (fig.  2,  page  4)  the  pipes  are  enclosed  in  an 
insulated  box  or  chamber  below  the  hover  floor  level.  Ventilator 
intakes  in  the  lower  part  of  this  chamber  admit  fresh  air  which  is 
heated  as  it  passes  up  through  the  pipes  and  is  then  conveyed  in  sepa- 
rate ducts  to  the  hovers.  The  temperature  of  each  hover  is  regulated 
by  adjusting  a  shutter  on  the  outlet  end  of  the  pipe  or  duct  carrying 
the  fresh  heated  air  to  that  hover.  This  system  has  a  further  advantage 
of  positively  ventilating  each  hover  by  the  introduction  of  fresh  warm 
air.2    It  is,  however,  rather  costly  to  install. 

Ample  Heat  Capacity. — The  ease  with  which  correct  temperature 
conditions  can  be  maintained  under  the  hover  will  largely  depend 
upon  the  cubical  content  of  the  brooder  pen,  the  heating  capacity  of 
the  heater  used,  and  the  coolness  of  the  weather.  The  investigations 
of  this  Station  show  that  the  larger  and  more  open  a  brooder  room  is, 
the  more  rapidly  the  air  of  the  room  absorbs  and  dissipates  the  heat 
from  the  hover.  To  maintain  a  sufficiently  high  hover  temperature 
under  such  conditions  in  winter  and  early  spring,  a  larger  fire  is 
required  and  more  fuel  consumed. 

In  a  brooder  room  of  a  certain  volume,  a  two-pipe  (one  inch  pipe) 
hot  water  system  might  supply  enough  heat  to  keep  even  baby  chicks 
comfortable  during  the  very  mild  weather  of  late  spring,  but  not  be 
able  to  do  so  in  the  colder  weather  of  January  and  February.  Yet  the 
first  two  or  three  months  of  the  year  represent  one  of  the  most  desir- 
able periods  in  which  to  hatch  pullets  that  will  produce  well  in  the 
fall  and  winter  of  the  pullet  year.     At  least  six  pipes  one  inch  in 

2  See  discussion  under  Ventilation  Without  Drafts,  page  1. 


8 


UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 


diameter  will  be  necessary  for  cold  weather  brooding,  and  fewer  than 
four  pipes  are  inadvisable  at  any  time  if  the  heating  system  is  to.  have 
enough  capacity  to  cope  with  sudden  cold  waves.  The  fire  can  be 
checked  to  lower  the  temperature  of  the  circulating  water  but  the  heat 
supplied  cannot  be  increased  beyond  the  radiating  capacity  of  the 
pipes  used. 

TABLE  1. 

Cost  of  Brooding  Chicks  by  10  Day  Periods  in  Units  of  Two 
Hundred  Fifty. 


Type  of  Hover 


1st 
period 

2nd 
period 

3rd 
period 

4th 
period 

5th 
period 

$1.36 

1.12 

1.00 

.75 

.62 

.99 

.83 

.86 

.90 

.27 

1.22 

1.54 

1.65 

1.03 

.83 

.68 

.62 

.44 

1.49 

.78 

.46 

.39 

.06 

3.04 

2.19 

.94 

.83 

.90 

2.52 

2.40 

1.24 

1.756 

1.219 

.931 

.698 

.458 

.70 

.488 

.372 

.279 

.183 

Total  cost 
per  100 
chicks 


Hot  water  (gas  heated) 

Coal  oil,  blue  flame  (make  1).. 
Coal  oil,  blue  flame  (make  2).. 
Coal  oil,  blue  flame  (make  3).. 

Electric  (make  1) 

Electric  (make  2) 

Coal  stove,  burning  coal 

Coal  stove,  burning  briquettes 
Average  per  unit  of  250  chicks 
Average  per  unit  of  100  chicks 


1.94 
1.54 

1.44 
1.27 
3.16 


Data  on  coal  stoves  is  limited  as  they  were  operated  only  a  short  time  but  further  data  is  being  taken . 
Cost  calculations  were  made  on  basis  of  coal  at  $26.00  per  ton,  carbon  briquettes  at  $22.00  per  ton, 
coal  oil  at  15  cents  per  gallon,  gas  at  90  cents  per  cubic  foot,  electricity  at  4  cents  per  K.W.H. 
The  electric  hovers  were  automatically  regulated;  the  other  types  were  manually  regulated. 
Curtains  were  used  with  electric  and  hot  water  hovers  only. 


In  a  similar  way,  success  in  operating  electric  brooders  is  largely 
influenced  by  the  volume  of  the  pen  in  which  they  are  used.  As  shown 
in  Table  1,  electric  brooder  ("Make  1")  was  operated  in  a  brooder 
room  8'  x  12'  x  6' 6"  high,  with  an  open  front  and  muslin  curtains,  at 
a  fuel  cost  which  compared  favorably  with  any  other  system  of  heat- 
ing used.  If  the  pen  had  been  larger  (of  greater  cubical  content) 
and  of  a  more  open  construction,  a  larger  heating  coil  would  have  been 
necessary  to  keep  the  chicks  comfortably  warm  and  a  greater  amount 
of  electricity  would  have  been  consumed. 

Portable,  blue  flame,  coal  oil  brooder  stoves  may  also  prove  too 
limited  in  heating  capacity  to  give  satisfactory  results  when  used 
for  early  brooding  in  large  open  front  laying  houses.  Such  a  house  is 
too  big  and  of  too  open  construction,  even  with  all  openings  closed, 
for  so  small  a  heater  to  suffice  during  the  colder  months. 


Circular  271] 


BROODING    CHICKS   ARTIFICIALLY 


Coal-burning  colony  brooder  stoves  do  have  enough  heat  capacity 
to  meet  such  conditions,  but  they  lack  flexibility  of  heat  control  and 
may  not  be  so  convenient  to  operate  as  oil  burners,  and  moreover, 
satisfactory  fuel  is  often  costly  and  difficult  to  obtain  in  this  state. 
The  fire  risk,  however,  is  small. 

A  decrease  in  the  size  and  volume  of  the  pen  will  decrease  the 
amount  of  heat  required  to  maintain  both  the  hover  and  the  air  of  the 
pen  at  optimum  temperatures  and  will  thereby  establish  housing  con- 
ditions in  which  electric  and  coal-oil  heated  brooders  of  limited  heating 
power  can  be  successfully  used.     The  use  of  auxiliary  stoves  to  take 


Fig.  5. — Shed  roof  laying  house  equipped  with  a  coal  brooder  stove  and 
used  for  brooding  chicks.  When  old  enough,  cockerels  can  be  removed  and 
pullets  taught  to  roost  on  droppings  boards. 

the  chill  from  the  air  of  the  brooding  room  or  pen  will  serve  the  same 
purpose  and  warm  the  air  of  the  brooding  room  to  50°  or  60°  F.,  so 
that  electric  and  coal-oil  brooders  can  be  successfully  used  in  the  colder 
months.  A  brooding  house,  however,  that  will  successfully  care  for 
early  as  well  as  late  hatches  and  permit  the  most  economical  use  of 
any  proved  brooding  device  of  reasonable  heating  power,  should  have 
as  low  a  cubical  content  as  effective  ventilation  and  convenience  of 
operation  will  allow. 

Economy  of  Heating. — Table  1  gives  very  full  data  on  the  con- 
sumption of  gas,  coal-oil,  coal  and  electricity  as  sources  of  heat  for 
brooding  purposes.  Gas  was  used  in  a  triple  copper  coil  gas  water 
heater,  which  heated  a  hot  water  pipe  system  brooder  house  75  feet 
long  and  16  feet  wide  with  a  5-foot  alleyway  and  brooding  pens  7  feet 
by  11  feet  in  size  (fig.  6).     The  coal-oil  hovers  used  were  the  42-inch 


10  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

size,  portable,  wickless,  blue  flame,  coal-oil  brooder  stoves  shown  in 
figure  7.  The  electric  brooders  were  similar  to  the  coal-oil  brooders 
except  for  the  fuel  used.  Accurate  weights  were  kept  of  all  oil  and 
coal  burned  and  the  gas  and  electricity  were  measured  by  meters. 

Cost  data  have  also  been  gathered  covering  the  brooding  operations 
of  a  number  of  commercial  poultry  farms.  It  was  found  that  during 
February  and  March,  it  cost  those  farms  brooding  with  coal,  $3.55 
for  the  fuel  to  brood  250  chicks,  to  50  days  of  age — the  same  period  and 
number  of  chicks  used  in  table  1.  The  farms  using  coal-oil  paid  $3.44, 
and  those  using  electricity  $3.14  for  each  250  chick  unit  during  the 
same  period. 

Reduced  to  the  basis  of  brooding  a  unit  of  100  chicks  to  8  weeks 
of  age,  coal  was  found  to  cost  $1.59 ;  coal-oil  $1.54 ;  and  electricity, 
$1.41.  The  average  cost  per  100  chicks  for  all  fuels  used  was  $1.53 
for  the  eight- week  period. 

Dependable  Heating  System  a  Necessity. — A  heating  system  for 
brooding  young  chicks  must  be  dependable.  It  must  burn  throughout 
the  night  without  material  fluctuation  and  maintain  the  needed  tem- 
perature under  the  hovers.  Tests  by  this  Station  of  a  number  of 
gravity  and  pressure  feed  coal-oil  burners  in  the  small  coal-burning 
hot  water  boiler  or  furnace  of  an  "overhead"  hot  water  brooding 
system,  have  indicated  that  these  burners  are  not  dependable  for 
such  work.  Anthracite  coal  has  proved  more  satisfactory  in  a  heater 
of  this  type.  In  much  larger  boilers  used  for  heating  very  long 
brooder  houses,  electrically  driven  burners  using  fuel  oil  would 
undoubtedly  give  dependable  service.  Such  large  burners,  however, 
would  be  of  value  only  on  exceptionally  large  poultry  farms. 

In  our  tests  with  the  smaller  oil  burners  that  are  designed  more 
especially  for  cook  stoves,  carbon  formed  at  the  fuel  outlet  after  five 
or  six  hours  of  burning  and  clogged  it  so  that  the  flame  slowly  became 
smaller  and  often  blew  out.  Every  effort  was  made  to  so  regulate  the 
draft  as  to  prevent  carbon  forming  at  the  fuel  outlet  but  without 
success.  If  this  should  occur  at  night,  not  only  would  the  chicks  be 
chilled  but  the  oil  would  also  continue  flowing  slowly  into  the  hot 
fire  box.  If  a  poultry  keeper,  upon  finding  the  fire  out  in  the  morning 
and  thinking  only  of  his  chicks,  should  try  to  light  the  burner 
before  thoroughly  airing  it  and  cleaning  the  ash  pit,  he  would  at 
least  risk  being  badly  burned  by  the  explosive  ignition  of  the  vaporized 
oil.  The  unvaporized  oil  in  the  ash  pit  might  also  cause  a  serious 
conflagration. 

Tests  with  portable,  blue  flame,  coal-oil  brooder  stoves  having  a 
visible  drip  feed  of  the  fuel  (sight  feed)  have  shown  them  unreliable 


Circular  271] 


BROODING    CHICKS    ARTIFICIALLY 


11 


in  maintaining  a  uniform  flame  throughout  the  night.  Since  the  sight 
feed  is  located  outside  of  the  hover,  the  number  of  drops  of  oil  per 
minute  decreases  as  the  brooding  room  becomes  cooler  during  the  night, 
due  to  the  fact  that  the  viscosity  of  coal-oil  increases  as  the  tempera- 
ture falls.  Consequently  the  dropping  becomes  more  sluggish.  Unless, 
in  cool  weather,  the  drops  per  minute  are  increased  to  produce  a 
maximum  flame  (top  of  flame  at  top  of  burner)  before  the  attendant 


Fig.  6. — Triple  copper  coil  gas  heater  used  to  heat  the  water  in  a  hot 
water  brooding  system.  Can  be  equipped  with  automatic  gas  regulator  to 
hold  temperature  of  hovers  at  any  desired  degree  of  heat. 


retires,  the  flame  may  decrease  sufficiently  in  the  night  to  chill  the 
chicks  or  even  go  out  and  perhaps  cause  a  heavy  mortality  from  the 
chicks  "piling  up."  Having  to  operate  with  so  high  a  flame  at  night 
becomes  objectionable  as  the  chicks  grow  larger  and  stronger,  because 
so  much  heat  is  neither  necessary  nor  beneficial,  and  means  a  serious 
waste  of  fuel.  The  latest  models  of  these  stoves  have  eliminated  the 
sight  feed  and  use,  instead,  a  very  dependable  method  of  flame  adjust- 
ment which  is  as  simple  in  operation  as  a  central  draft  oil  lamp. 


12  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

Simplicity  and  Durability  of  Construction, — Simplicity  of  con- 
struction in  brooding  equipment  makes  for  durability  and  convenience 
in  operation.  There  are  fewer  parts  to  be  cared  for,  to  get  out  of 
order,  and  to  cause  trouble.  The  burner  of  the  heating  system  should 
be  simple  in  design  and  easy  to  clean.  In  the  case  of  electric  hovers, 
the  heating  coils  should  be  easy  of  access  at  least  for  the  emergency 
repairing  of  open  and  short  circuits.  The  use  of  standard  materials, 
as  far  as  possible,  is  also  very  desirable  in  order  that  new  parts  can  be 
readily  obtained  at  local  supply  houses. 

The  initial  installation  of  dependable  materials  is  the  kind  of 
durability  insurance  that  costs  the  least.  Flimsy  or  inadequate  con- 
struction may  lower  the  initial  expense  but  is  costly  in  the  end. 
Brooding  equipment  is  in  constant  service  twenty-four  hours  a  day 
during  the  rearing  season  and  is  subject  to  more  or  less  hard  usage. 
Portable  brooders  may  be  subject  to  considerable  moving.  The  best  of 
materials  for  each  purpose  is  none  too  good  if  maximum  efficiency  is 
to  be  obtained. 

Ease  in  Cleaning. — In  planning  a  brooder  house,  consideration 
should  be  given  to  the  ease  with  which  all  parts  can  be  cleaned  and 
disinfected,  for  cleanliness  and  sanitation  are  very  essential  to  the 
continued  health  and  thrifty  growth  of  young  stock.  It  is  axiomatic 
that  the  harder  it  is  to  do  a  thing,  the  less  often  it  will  be  done.  A 
brooder  house  should  be  cleaned,  scrubbed,  hosed  out,  and  disinfected 
at  least  once  each  year.  In  this  work  a  well  drained  floor  is  a  great 
convenience.  With  a  dirt  floor  a  thorough  cleaning  of  this  kind  cannot 
be  done  without  converting  the  floor  into  a  mud  hole.  Board  floors 
absorb  much  water,  tend  to  curl  in  drying,  and  make  an  uneven  floor 
surface.  Unless  a  board  floor  is  laid  with  a  slight  slope  so  that  it 
drains  well,  the  water  used  in  cleaning  the  brooder  house  must  be 
laboriously  shoveled  and  swept  out.  A  concrete  floor  costs  no  more 
than  a  well-laid  board  floor.  It  has  a  hard,  smooth  surface  which 
is  easily  cleaned  and  unlike  a  wood  floor,  the  surface  remains  smooth 
and  free  from  shovel-catching  irregularities.  It  is  practically  ever- 
lasting and  easily  laid  with  a  slope  so  that  all  water  will  drain  off  as 
fast  as  it  is  poured  on. 

The  size  of  the  pen  in  relation  to  the  use  of  a  shovel  and  broom, 
ease  of  removing  dirty  litter  and  manure  and  bringing  in  clean  litter, 
the  use  of  portable  appliances  which  can  be  readily  gotten  out  of  the 
way,  convenience  of  arrangement  of  the  hover  for  cleaning,  are  all 
items  deserving  careful  consideration  in  planning  a  brooding  house 
requiring  a  minimum  of  time  and  effort  to  keep  clean. 


Circular  271]  brooding  chicks  artificially  13 

Convenience  of  Operation. — Ease  of  cleaning  the  brooder  house 
is  but  one  factor  in  convenience  in  caring  for  chicks.  Convenience  in 
inspecting  the  interior  of  the  hover,  regulating  the  heat  and  ventila- 
tion, reading  temperatures,  feeding  and  watering  are  other  items  that 
have  a  direct  bearing  on  the  effort  required  to  perform  the  work. 
A  sink  and  drain  board,  for  example,  in  the  walkway  (fig.  8)  of  a 
long  house  is  a  great  convenience  in  cleaning  buttermilk  and  water 
founts.  A  hover  which  raises  up  is  much  more  easily  inspected  than 
one  which  the  attendant  must  get  on  his  hands  and  knees  to  peer 


Fig.  7. — Wickless  blue  flame  coal-oil  brooder  stove  in  operation.  The  can 
of  water  placed  over  the  hole  in  the  top  of  the  galvanized  iron  canopy  is  used 
to  prevent  the  wasting  of  heat  through  this  opening  and  to  increase  the 
humidity  of  the  brooder  room. 

under.  The  number  of  gates  or  doors  to  be  opened  in  carrying  appli- 
ances, feed,  litter,  and  tools  in  and  out  of  the  pens  may  greatly  reduce 
efficiency.  A  house  that  is  elevated  above  ground  so  that  the  attend- 
ant must  constantly  carry  loads  up  and  down  two  or  three  steps  or 
push  a  wheelbarrow  up  and  down  a  steep  incline  can  hardly  be  con- 
sidered convenient.  That  construction  and  arrangement  is  best  which 
gives  the  maximum  of  convenience  at  the  minimum  expense. 

Size  of  Hover. — The  hover  should  be  large  enough  to  accommodate 
all  of  the  chicks  at  one  time  without  crowding.  On  cool  nights  the 
room  temperature  will  fall  rather  low,  thereby  causing  young  chicks 


14  UNIVERSITY   OF    CALIFORNIA — EXPERIMENT   STATION 

to  remain  more  closely  under  the  hover  than  they  would  on  warm 
nights.  Seven  square  inches  of  hover  space  per  chick  will  meet  this 
requirement.  A  hover  42"  in  diameter  would,  on  this  basis,  have  a 
capacity  of  200  chicks  and  one  52"  in  diameter  would  comfortably 
care  for  300  chicks. 

Late  in  the  spring,  however,  when  both  the  nights  and  days  are 
much  warmer,  young  chicks  will  not  require  so  much  artificial  heat 
to  keep  them  comfortable.  They  will  not  remain  so  closely  under  the 
hover  at  night,  but  will  spread  out,  since  the  heat  radiated  from  the 
hover  will  be  dissipated  and  cooled  less  rapidly  by  the  air  of  the 
pen  than  in  cool  weather.  Under  such  conditions  five  or  six  square 
inches  of  hover  space  per  chick  may  be  sufficient. 

The  manufacturer's  rating  of  factory-built  brooding  equipment 
should  be  checked  with  the  data  given  above  to  insure  the  buyer's 
obtaining  sufficient  hovers  to  meet  his  needs  at  different  seasons.  It  is 
much  better  to  have  the  hover  a  little  large  than  too  small  for  the 
number  of  chicks. 

Scratching  Space  Outside  the  Hover. — Exercise,  and  fresh  air  are 
indispensable  to  sturdy  growth.  The  more  exercise  chicks  can  be 
induced  to  take  in  a  cool,  well- ventilated  pen  (fig.  9),  the  better  they 
will  thrive.  At  the  same  time  they  must  be  provided  with  a  warm 
hover  in  which  to  go  when  they  begin  to  feel  cold. 

A  scratching  floor  large  enough  to  give  the  chicks  " elbow  room" 
and  covered  with  a  good  scratching  litter,  stimulates  exercise.  It 
provides  ample  space  away  from  the  warm  and  more  enervating 
atmosphere  of  the  hover  where  chicks  can  run  and  scratch,  fill  their 
lungs  with  fresh  cool  air,  quicken  and  strengthen  digestion,  become 
used  to  normal  temperatures,  and  make  strong,  rapid  growth. 

Toe-picking  is  a  pernicious  habit  undoubtedly  induced,  at  first, 
by  curiosity  concerning  the  moving  toes  of  other  chicks.  Chicks  have 
a  natural  taste  for  animal  products  and  once  they  draw  blood,  they 
seem  to  persist  in  the  practice  and  transmit  it  to  others.  Chicks 
seriously  toe-picked  apparently  suffer  a  severe  nervous  shock  which 
is  fatal  in  a  majority  of  cases.  The  most  effective  measures  to  take 
against  toe-picking  are  prevention  and  the  immediate  removal  of 
toe-picked  chicks  to  a  separate  pen  or  pens. 

The  practice  of  toe-picking  is  fostered  (1)  by  crowding  chicks 
(instead  of  giving  them  roomy  quarters)  and  (2)  by  over-feeding. 
Small  pens  keep  chicks  so  close  together  that  their  attention  is  apt 
to  become  focused  on  each  other's  toes.  Keeping  chicks  slightly 
hungry  and  busy  in  pens  and  yards  large  enough  to  keep  them  inter- 
ested in  other  directions  represents  the  ounce  of  prevention  that  is 


Circular  271] 


BROODING    CHICKS    ARTIFICIALLY 


15 


worth  a  pound  of  cure.  Do  hen-reared  chicks  toe-pick?  Are  they 
crowded  in  large  numbers  into  small  pens  and  pocket  handkerchief 
runs? 

A  brooder  pen  with  a  total  floor  area,  including  the  hover,  of 
one-half  square  foot  per  chick  is  not  too  large  for  chicks  less  than 
five  weeks  of  age.  The  area  per  chick  should  then  be  increased  to 
allow  for  the  increase  in  growth.  This  is  usually  done  by  removing 
the  cockerels  to  separate  pens  since  a  normal  hatch  contains  approxi- 
mately one-half  females  and  one-half  males.  Ample  room  for  further 
growth  is  thus  provided. 


muslin  curtain 


Fig.  8. — Open  front  walkway  brooder  house  in  which  any  kind  of  hover  may 
be  used  as  indicated.  Pens  can  be  thrown  together  by  raising  boards  A  if  it 
is  desired  to  use  one  room  for  the  hover  and  one  as  a  cool  room. 

Size  of  the  Pen. — The  number  of  chicks  to  be  brooded  in  each 
pen  has  a  direct  bearing  on  the  size  of  the  pen.  If  one-half  square 
foot  of  floor  space  per  chick  is  allowed,  100  chicks  would  require  a 
pen  containing  50  square  feet;  and  200  chicks  a  pen  containing  100 
square  feet  of  floor  space.  A  brooder  pen  16  feet  deep,  for  example, 
would  need  to  be  only  3%  feet  wide  for  100  chicks — (too  narrow  a 
width  for  convenience),  6*4  feet  wide  for  200  chicks,  and  so  on. 

This  Station  has  found  that  as  the  size  of  the  flock  brooded 
together  is  increased,  other  things  being  equal,  the  mortality  tends 
to  increase.  Strong  chicks  will  always  crowd  the  weaker  ones  away 
from  the  feed,  trample  on  them,  pick  at  them  and  otherwise  manifest 
their  superior  strength.  Increasing  the  number  of  chicks  kept  together 


16  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

emphasizes  this  condition.  The  "law  of  the  survival  of  the  fittest" 
operates  with  increasing  effect  as  the  number  of  chicks  competing  with 
each  other  in  one  flock  is  multiplied.    . 

The  investment  and  labor  cost  per  chick  is  reduced,  it  is  true,  as 
the  size  of  the  flock  is  increased,  but  what  is  gained  if  the  vigor  of  the 
flock  is  impaired,  rate  of  growth  checked,  death  loss  raised,  and  a 
greater  number  of  runts  and  culls  produced?  Extended  analysis  of 
the  decrease  in  cost  of  labor,  investment,  and  so  on  obtained  by  enlarg- 
ing the  size  of  flocks  of  chicks  brooded  together,  as  compared  with  the 
decrease  in  returns  resulting  from  increased  mortality,  greater  num- 
ber of  culls,  etc.,  has  shown  that  approximately  200  chicks  is  the  most 
economical  number  that  can  be  reared  in  one  flock. 

The  most  important  factor  for  success  in  rearing  chicks  in  any 
size  of  flock,  however,  is  the  skill  and  attention  of  the  person  caring 
for  them.  Some  poultry  keepers  are  successful  in  rearing  chicks  in 
rather  large  flocks  while  others  with  less  natural  ability,  skill,  and 
experience  are  unsuccessful  in  small  units.  It  is  a  well  recognized 
fact  that  as  the  size  of  the  flock  brooded  is  enlarged,  greater  atten- 
tion and  skill  are  required  to  prevent  increasingly  poor  results  in 
both  quality  and  quantity. 

■  System  of  Yarding. — The  size  and  the  "range  quality"  of  the 
yards  exert,  perhaps,  a  more  positive  influence  on  the  strong  growth 
of  young  stock  after  they  are  a  few  weeks  old  (confined  stock 
excepted)  than  the  size  of  the  pens  within  the  brooding  house,  because 
the  birds  will  spend  most  of  their  time  out  of  doors  if  conditions  are 
at  all  favorable.  "Range  quality"  refers  to  the  available  supply  of 
natural  shade  and  green  pasturage  and  to  the  condition  of  the  soil 
which,  in  the  case  of  yards  that  are  bare  all  or  a  part  of  the  time, 
should  be  kept  loose  and  well  pulverized  by  frequent  cultivation.  The 
most  successful  way  to  rear  poultry,  so  far  as  sturdy,  rapid  growth 
is  concerned,  is  under  conditions  of  free  range  where  the  growing 
fowls  have  freedom  of  action,  gain  exercise  in  ranging  widely  over 
the  fields,  and  pick  up  a  variety  of  food. 

'.~  Succulent,  green  pasturage,  whether  on  free  range  or  in  large 
yards;  will  stimulate  a  more  vigorous  growth  in  young  stock  in  hot 
weather  than  bare-  range  or  yards  even  though  an  abundant  •  amount 
of  tender  green  stuff  is  cut  and  fed  daily  in  green feed  hoppers.  '  To 
grow  green  crops  such  as  alfalfa  and  Sudan  grass  for  poultry  pasturage 
purposes  in  most  sections  of  California,  however,  irrigation  is  required. 
To  prevent  the  fowls  from  seriously  injuring  such  pasturage  by  too 
close  cropping  of  the  tender  growth,  not  more  than  300  birds  half 
grown  or  larger  can  safely  be  run  per  acre. 


Circular  271]  brooding  chicks  artificially  17 

A  double  yard  system  with  large  yards  which  can  be  irrigated 
in  summer,  most  closely  approaches  free  range  conditions  in  the 
results  obtained.  With  large  double  yards  attached  to  each  brooder 
pen,  one  yard  can  be  plowed  and  planted  to  some  quick  growing 
crop,  such  as  barley  in  the  cooler  months  and  Sudan  grass  in  summer, 
while  the  chickens  run  in  the  other.  When  the  green  crop  has 
attained  a  height  of  about  eight  inches,  the  chickens  are  turned  in  on 
it  and  the  other  yard  is  then  irrigated,  plowed,  and  sowed.  Cropping 
supplies    young,    succulent    pasturage    for    the    fowls;    the    manure 


Fig.  9. — Showing  further  details  of  the  arrangement  and  construction  of 
the  front  windows  and  muslin  curtain  frame  illustrated  in  Fig.  8.  The  curtain 
is  hinged  at  the  top  and  folds  up.  This  is  an  excellent  front  arrangement  for 
any  kind  of  brooder  house. 

deposited  over  the  yards  instead  of  being  left  as  a  medium  for  the 
propagation  and  spread  of  internal  parasites  and  disease  germs,  is 
utilized  as  fertilizer ;  and  the  frequent  cultivation  keeps  the  soil  loose 
and  pulverized,  thoroughly  aerated,  and  in  condition  to  be  acted 
upon  by  the  sun 's  rays.  Dry  air  and  sunlight  are  powerful  germicides 
and  disease-preventing  agencies.  The  loose,  moist  soil  stimulates 
quick,  tender  growth  of  health-promoting  greenstuff  and  provides 
favorable  conditions  for  dusting. 

In  figure  10  is  illustrated  a  free  range  system  of  rearing  chicks 
which  works  splendidly  where  large  fields  or  orchards  are  available. 


18  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION 

The  houses  shown  are  8  feet  by  8  feet  in  size  and  of  knock-down  con- 
struction. They  can  be  knocked  down  by  two  men  in  twenty  minutes, 
loaded  on  a  wagon,  hauled  to  a  new  location  and  set  up  again  in 
another  twenty  minutes.  Houses  of  this  type  may  be  built  on  4  inch 
by  6  inch  runners  and  without  a  floor.  Then  instead  of  cleaning  out 
the  night  droppings  at  intervals,  each  house  may  be  hauled  a  short 
distance  to  a  clean  site. 

The  houses  can  be  set  up  near  the  dwelling  in  spring  and  used  for 
brooding.  Each  house  will  hold  a  maximum  of  200  chicks.  Coal-oil  or 
electric  hovers  can  be  used.  When  the  chicks  no  longer  require  arti- 
ficial heat,  the  sexes  should  be  separated  and  the  cockerels  put  in 
quarters  where  they  can  be  grown  and  finished  for  market.  The 
houses  with  the  pullets  can  then  be  placed  along  the  edge  of  an  alfalfa 
field  or  orchard.  If  the  cockerels  are  put  on  range  too,  they  should 
be  widely  separated  from  the  pullets. 

Only  one  house  at  a  time  should  be  moved  out  on  the  range  and 
the  pullets  should  be  kept  confined  for  two  days  before  they  are 
allowed  to  run  at  large.  If  they  are  not  confined  at  first,  they  will 
all  return  to  the  place  from  which  the  house  was  moved  and  the 
poultry  keeper  will  have  the  exasperating  task  of  catching  them  at 
night  and  putting  them  back  in  their  house. 

As  soon  as  the  first  lot  of  young  pullets  moved  has  been  running 
out  for  two  or  three  days  and  all  go  to  roost  nicely  each  night,  a 
second  house  of  pullets  may  be  moved  out,  but  it  should  be  placed 
at  least  fifty  feet  from  the  first  one.  This  second  lot  of  pullets  should 
be  kept  confined  two  days.  Then  the  birds  in  the  first  house  should 
be  confined  for  the  first  two  days  that  the  second  lot  is  let  out.  Other- 
wise, the  two  lots  will  mix  and  perhaps  all  or  nearly  all  will  use  the 
same  house.  The  practice  described  here  will  teach  each  lot  of  pullets 
to  roost  in  its  own  house.  As  each  new  house  is  brought  out,  the  birds 
should  be  confined  for  two  days  and  then  the  other  groups  of  birds 
on  that  range  kept  confined  for  two  days  while  the  new  lot  learns  to 
run  out  and  return  to  its  own  house. 

If  the  houses  are  located,  for  example,  between  a  grain  stubble 
field  and  a  field  of  alfalfa  and  close  to  an  orchard,  the  birds  will  have 
ideal  conditions.  They  can  range  the  stubble  and  alfalfa  fields  night 
and  morning  for  grain,  insects  and  green  herbage  and  work  in  the 
shade  of  the  trees  in  the  hot  part  of  the  day.  The  pullets  will  make 
a  rapid,  hardy  growth  and  pick  up  most  of  their  living,  requiring  only 
protection  from  predatory  birds  and  animals  and  plenty  of  fresh 
water. 


Circular  271] 


BROODING    CHICKS   ARTIFICIALLY 


19 


This  system  of  rearing  chickens  requires  no  fencing  which  would 
interfere  with  plowing  and  irrigating,  in  orchards  or  cropped  fields, 
and  is,  therefore,  very  convenient  for  use  on  the  farm  or  in  connec- 
tion with  orchards.  It  has  the  further  advantage  of  giving  the  fowls 
free  range  and  enabling  them  to  pick  up  a  large  part  of  their  feed 
in  the  fields.  In  some  locations  the  birds  may  be  exposed  to  greater 
danger  from  hawks,  weasels,  and  other  enemies  than  would  be  the 
case  if  they  were  yarded,  but  as  a  rule,  the  most  profitable  way  to  rear 


Fig.  10. — Colony  rearing  houses  on  free  range.     A  large  alfalfa  field  is  at 
the  rear  of  the  line  of  houses. 


chickens  is  under  good,  free  range  conditions.  Laying  hens  can  also 
be  kept  in  this  way.  If  the  movable  houses  are  to  be  used  for  brood- 
ing young  chicks  or  for  laying  hens  in  winter  however,  they  should 
have  floors  to  make  them  more  sanitary  and  convenient  to  clean  for 
they  cannot  be  moved  as  frequently  in  winter  as  in  summer. 

Summer  Shade. — Good  shade  should  be  provided  in  the  brooder 
yards  in  summer  to  induce  the  chicks  to  spend  as  much  time  out  of 
doors  as  possible.  Abundant  exercise  in  the  fresh,  pure,  outdoor  air 
promotes  sturdy  growth,  the  chicks  become  more  quickly  accustomed 
to  cooler  temperatures  and  the  heat  of  the  hover  can  accordingly  be 
reduced  more  rapidly.  Natural  shade  is  more  desirable  than  arti- 
ficial shade.     Trees  are  excellent  because  they  give  a  dense,  wide- 


20  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION 

spreading  shade  without  restricting  the  free  circulation  of  air.  For 
narrow  nursery  brooder  yards,  vines  trained  over  the  tops  of  the  yards 
serve  very  well.  The  weeping  mulberry  headed  high  and  trained 
over  the  tops  of  narrow  yards  also  provides  good  shade. 

FEEDING   YOUNG   CHICKS 

First  Care  of  Chicks. — The  interior  of  the  brooder  pen,  as  well  as 
all  equipment  and  utensils,  should  be  thoroughly  washed,  scrubbed, 
and  disinfected  a  few  days  in  advance.  When  thoroughly  dry,  the 
floor  around  the  hover  should  be  lightly  covered  with  sifted  light  or 
dark  sand  and  the  hover  temperature  regulated  to  between  90°  and 
95°  F.,  with  the  thermometer  near  the  outer  edge  of  the  hover  and 
the  center  of  the  thermometer  bulk  two  inches  above  the  floor.  Eight- 
inch  boards  or  one-inch  mesh  wire  netting  one  foot  wide  should  be 
used  to  form  a  small  enclosure  around  the  hover  for  the  first  three  or 
four  days  to  prevent  the  chicks  from  getting  too  far  away  until  they 
learn  to  use  it.  In  cool  weather  the  wire  netting  ring  should  be  faced 
with  burlap  sacks  cut  open  and  sewed  to  the  wire. 

In  large  brooder  pens,  the  enclosure  may  be  enlarged  a  little  each 
day  in  order  to  gradually  accustom  the  chicks  to  the  larger  area.  In 
small  pens  this  is  not  necessary. 

About  twenty-four  hours  after  the  hatch  is  completed,  the  chicks 
should  be  taken  from  the  incubator,  placed  under  the  hover  in  the 
brooder  pen,  and  given  fresh  water  to  drink.  It  is  better  to  move 
them  into  the  brooder  in  the  morning  so  that  they  can  be  closely 
watched  for  the  first  five  or  six  hours. 

No  solid  food  should  be  given  until  the  chicks  are  from  sixty  to 
seventy-two  hours  old.  At  hatching,  a  good  deal  of  yolk  material 
still  remains  undigested  in  the  chick's  abdomen  and  should  be 
absorbed  before  the  digestive  organs  are  required  to  handle  other  food. 

If  the  common  type  of  chick  fountain  having  a  round  pan  and 
holding  from  one  and  one-half  to  two  quarts  of  water  is  used,  one  such 
fountain  should  be  provided  for  each  100  chicks.  Fountains  with 
conical  tops  are  better  than  those  with  flat  tops  because  the  chicks 
cannot  perch  on  them  and  foul  the  fountain  and  water  with  droppings. 
Fountains  should  be  washed  at  least  once  a  day  and  the  water  changed 
twice  a  day. 

Chicks  should  be  allowed  in  the  yards  as  soon  as  possible.  Contact 
with  the  ground  and  exercise  out  of  doors  will  be  found  to  promote 
a  more  rapid  and  hardy  growth.  Just  how  soon  after  being  put  in 
the  brooder  they  should  be  allowed  in  the  yards  will  depend  entirely 
on  weather  conditions.    The  cooler  the  weather,  the  older  and  stronger 


CIRCULAR  271]  BROODING    CHICKS    ARTIFICIALLY  21 

they  must  be  to  withstand  the  outdoor  air  without  becoming  chilled. 
In  winter  it  may  not  be  safe  to  allow  them  in  the  yards  until  they  are 
four  or  five  weeks  old  and  then  only  during  the  warm  part  of  the  day, 
at  first.  In  May  they  can  perhaps  be  out  of  doors  during  the  middle 
of  the  day  when  three  or  four  days  old.  They  should  be  kept  indoors  in 
rainy  weather  at  any  time  of  the  year. 

Feeding  Milk. — If  it  can  be  obtained  at  a  reasonable  cost,  butter- 
milk or  sour  skimmilk  may  be  given  to  chicks  from  the  time  they  are 
removed  to  the  brooder.  Sour  skimmilk  will  be  consumed  more  evenly 
if  the  curd  is  broken  into  fine  particles  by  vigorous  agitation  with  a 
dasher  before  being  fed.  Milk  may  be  given  in  the  morning  and 
water  in  the  afternoon,  or  both  may  be  made  available  during  the 
whole  day.  If  mash  is  kept  before  young  chicks,  however,  milk  should 
not  be  fed  after  3  p.m.  Chicks  having  access  to  both  mash  and  milk 
in  the  late  afternoon  are  prone  to  over-eat  of  these  foods  before  going 
to  bed.  Digestion  is  slower  at  night  than  during  the  day  when  the 
chicks  are  vigorously  exercising,  and  a  mushy  mixture  of  these  foods 
in  the  hot  interior  of  the  crop  at  this  time  may  ferment  before  it  can 
be  digested.  The  result  is  a  condition  of  colic  or  sour  crop  which  is 
generally  fatal  to  chicks  under  three  weeks  of  age  and  weakening  to 
older  chicks. 

Young  stock  which  are  fed  all  the  buttermilk  or  sour  skimmilk 
they  will  drink  need  no  other  animal  food  such  as  meatscrap,  fish- 
scrap,  or  bonemeal  in  their  diet.  If  only  a  small  amount  of  milk  can 
be  fed,  however,  animal  feed  should  not  be  eliminated  from  the  ration 
but  merely  reduced  in  quantity.  One  pound  of  commercial  meatscrap 
or  fishscrap  should  be  considered  equal  to  fifteen  pounds  of  fresh 
buttermilk. 

If  chicks  are  physicked  from  drinking  too  eagerly  or  if  they 
develop  sour  crop,  the  milk  should  be  fed  in  the  morning  only.  Some 
lots  of  chicks  may  develop  an  abnormal  appetite  for  milk ;  this 
should  be  curbed  by  feeding  more  sparingly.  Milk  should  be  fed  in 
crocks  or  enameled  pans.  The  lactic  acid  corrodes  galvanized  iron 
pans. 

Milk  Treatment  for  Coccidiosis. — The  feeding  of  fresh  buttermilk 
or  sour  skimmilk  is  the  most  effective  treatment  which  has  yet  been 
used  for  the  control  of  coccidiosis3  in  growing  chicks. 

Coccidiosis  is  an  infectious  disease  caused  by  a  protozoan  organism 
which  invades  the  caeca  and  intestinal  tract  in  young  stock.  Among 
the  most  prominent  symptoms  are  a  rapid  loss  of  vitality  throughout 
the  flock,  huddling  together  in  corners  and  under  the  hover  with  every 

3  For  a  more  detailed  discussion  of  coccidiosis,  the  reader  is  referred  to 
Circular  No.  251,  California  Agricultural  Experiment   Station. 


22  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION 

appearance  of  being  cold,  the  passing  of  bloody  droppings,  and  a  sud- 
den increase  in  mortality.  Bloody  droppings  are  usually  evident  only 
in  acute  outbreaks.  This  disease  might  be  termed  a  young  stock 
disease  because  it  rarely  occurs  in  chicks  less  than  two  or  more  than 
sixteen  weeks  of  age. 

A  post-mortem  examination  of  dead  chicks  usually  shows  enlarged 
caeca  whose  contents  are  pasty  or  semi-liquid  and  brown,  reddish 
brown,  or  bloody.  The  outer  walls  of  the  caeca  may  show  flecks  of 
red  indicating  inflamed  areas.  Frequently  this  inflammation  extends 
into  the  intestines. 

As  soon  as  the  disease  is  discovered,  the  feeding  of  mash  and 
water  should  be  stopped  and  the  birds  given  only  a  scanty  feeding 
of  grain  morning  and  night.  Crocks  of  buttermilk  or  sour  skimmilk 
should  now  be  kept  constantly  before  the  chicks.  Green  feed  is  fed 
as  usual. 

Taking  away  all  drinking  water  induces  a  heavy  consumption  of 
milk  which  acts  as  a  strong  laxative  and  causes  the  chicks  to  pass  large 
amounts  of  very  watery  excreta.  As  a  result,  the  floor  of  the  brooder 
pen  becomes  very  damp  and  must  be  cleaned  daily  and  re-strawed 
with  just  enough  litter  to  absorb  the  moisture.  Daily  cleaning  is  also 
valuable  in  checking  coccidiosis,  since  this  disease  is  spread  by  the 
infected  droppings  of  diseased  birds.  Cleaning  out  the  soiled  litter 
removes  the  infected  excreta  before  it  can  do  any  serious  harm  in 
intensifying  the  ravages  of  the  disease. 

Since  buttermilk  has  considerable  food  value,  the  treatment  not 
only  checks  the  disease  rapidly  but  the  chicks  may  make  a  considerable 
gain  in  weight  by  the  end  of  the  treatment. 

The  treatment  should  be  continued  for  about  ten  days  or  until  all 
signs  of  the  disease  have  disappeared.  Then  the  feeder  can  begin  to 
slowly  bring  the  chicks  back  to  the  normal  method  of  feeding.  The 
feeding  of  milk  alone  may  now  be  limited  to  the  morning  period  for 
two  or  three  weeks  and  both  milk  and  water  given  in  the  afternoon. 
In  resuming  the  feeding  of  mash,  it  should  be  fed  for  only  one  hour 
at  noon  for  the  first  three  days  and  the  mash  feeding  period  then 
lengthened  one  hour  every  three  days  until  it  is  being  fed  normally. 
The  usual  method  of  feeding  grain  may  be  resumed  in  like  manner. 

Feeding  Grain. — When  from  60  to  72  hours  old,  chicks  are  fed  a 
chick  grain  mixture  on  a  board  or  in  a  shallow  chick  hopper  (fig.  11) 
placed  just  outside  of  the  hover.  The  following  mixture  is  recom- 
mended : 

33%%  cracked  wheat  (by  weight). 
33%%  fine  cracked  corn. 
33%%  steel-cut  oats. 


Circular  271]  BROODING    CHICKS   ARTIFICIALLY  28 

The  grain  mixture  should  be  left  before  the  chicks  till  they  learn 
to  eat  readily.  This  will  require  one  or  two  days  because  at  first 
they  will  pick  considerably  but  swallow  little.  On  the  second  day  the 
grain  hoppers  can  usually  be  removed  at  noon  and  a  small  amount 
of  grain  then  sprinkled  over  the  sand  just  outside  the  hover.  If  this 
grain  is  eaten  readily,  more  should  be  given  at  four  in  the  afternoon 
and  again  the  next  morning,  feeding  each  time  only  what  will  be 
cleaned  up  in  about  an  hour.  The  chicks  should  be  sufficiently  strong 
and  active  by  this  time  that  they  can  be  fed  grain  in  a  scratching 
litter.  This  litter  may  consist  of  fine-cut  alfalfa  hay  spread  lightly 
over  the  scratching  floor.  The  grain  should  be  scattered  in  the  litter 
three  times  a  day  till  the  feeding  of  mash  is  begun,  when  the  noon 
feeding  of  grain  should  be  omitted.  When  the  birds  are  about  four 
or  five  weeks  of  age,  a  mixture  of  one-half  cut  alfalfa  hay  and  one- 
half  cut  straw  may  be  used  in  place  of  the  straight  alfalfa  litter,  and 
a  few  weeks  later  whole  straw,  if  not  too  coarse,  can  be  used.  Planer 
shavings  are  also  used  as  a  litter  material,  but  are  likely  to  pack  too 
much  and  do  not  conceal  the  grain.  Moreover  they  draw  dampness  in 
wet  weather. 


Fig.  11. — Chick  mash  hopper.  A  hopper  34%  inches  long,  5  inches  wide, 
and  iy2  inches  high,  inside  dimensions,  is  a  very  convenient  size.  The  %-inch 
mesh  hardware  cloth  grid  prevents  the  chicks  from  wasting  feed  by  scratching 
it  out  of  the  hopper. 

The  depth  of  the  scratching  litter  should  be  increased  as  the  chicks 
grow  older,  out  care  must  be  taken  not  to  get  it  so  deep  as  to  prevent 
their  digging  to  the  bottom  of  it  easily,  nor  so  shallow  as  to  permit 
the  chicks  to  get  the  grain  without  effort.  The  scratching  litter,  if 
used  wisely,  is  an  effective  means  of  supplying  brooder  chicks  with 
healthful  exercise.  Exercise  aids  in  developing  sturdy  chicks  that 
make  rapid  growth  and  is  one  of  the  most  valuable  preventives  of 
disease. 

Approximately  one-half  pint  of  grain  should  be  given  at  a  feeding 
to  each  one  hundred  chicks  under  one  week  of  age.  This  amount  may 
be  increased  from  week  to  week  as  the  birds  grow  larger.  If  grain  is 
found  in  the  litter  at  feeding  time,  the  amount  given  at  a  feeding 
should  be  reduced.  If  all  the  grain  has  been  scratched  out  of  the 
litter   and  the  chicks   act   exceptionally   hungry   at   meal   time,   the 


24  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

amount  of  grain  should  be  increased.  They  should  be  fed  only  enough 
grain  to  keep  them  growing  thriftily  and  their  appetites  keen.  They 
should  come  to  each  meal  reasonably  hungry. 

Changing  from  Chick  to  Growing  Grains. — If  steel-cut  oats  are 
too  costly  to  be  used,  cracked  hulled  barley,  cracked  Milo  or  cracked 
Egyptian  corn  can  be  substituted.  However,  no  better  grain  than 
hulled  oats  can  be  used  as  a  starting  feed  for  the  first  few  weeks  of  a 
chick's  life,  After  this  period  other  grains  may  be  used  to  replace 
the  oats.  Steel-cut  oats  are  preferable  to  rolled  oatmeal,  or  so-called 
breakfast  rolled  oats,  because  the  latter  are  likely  to  become  sticky 
when  moistened  by  the  juices  in  the  crop  and  ' '  ball  up ' '  into  a  cohesive 
mass,  difficult  to  digest,  especially  when  fed  alone. 

Cracked  grains  should  be  replaced  by  whole  grains,  in  the  case  of 
small  grains  like  wheat,  milo,  oats  and  barley,  at  six  weeks  of  age 
when  the  chicks  are  large  enough  to  eat  them.  Fine  cracked  corn 
should  not  be  replaced  by  the  coarse  cracked  grade,  however,  until 
two  or  more  weeks  later.  Whole  barley  may  be  added  to  the  grain 
ration  when  the  chicks  are  from  ten  to  twelve  weeks  old.  It  should 
be  used  moderately  at  first  and  gradually  increased,  but  the  total 
amount  used  should  not  exceed  fifty  per  cent  of  the  grain  ration. 

One  should  not  be  too  hasty  in  changing  from  fine  to  coarser 
cracked  and  whole  grains.  This  is  particularly  true  with  yellow  corn 
because  different  lots  of  the  coarse  cracked  grade  may  vary  consid- 
erably in  coarseness.  The  larger  particles  of  a  very  coarse  lot  might 
prove  injurious.    A  little  care  in  this  matter  is  well  worth  while. 

Feeding  Mash. — When  chicks  are  seven  days  old,  the  feeding  of  a 
dry  mash  is  usually  beg'un.  The  following  formula  and  method  of 
feeding  are  recommended : 

25%  bran. 
25%  shorts. 
20%  yellow  corn  meal. 
10%  soybean  meal. 
15%  meatscrap. 

.5%  very  finely  ground  bonemeal. 
2|%  granulated  chick  charcoal. 

'■■  Note.— -All'  proportions  are  by  weight.  The  charcoal  is  fed  in 
addition  to  the  100%  mixture  of  feed  stuffs. 

At    7  days  old  begin  feeding  dry  mash  from  10  a.m.  to  11  a.m. 
At  14  days  old  begin  feeding  dry  mash  from  10  a.m.  to  12  m. 
At  28  days  old  begin  feeding  dry  mash  from  10  a.m.  to    1  p.m. 
At  42  days  old  begin  feeding  dry  mash  from  10  a.m.  to    2  p.m. 


Cieculas  271 


BROODING    CHICKS    ARTIFICIALLY 


25 


For  pullets  and  cockerels  that  are  to  be  raised  for  laying  and 
breeding,  a  well  formulated  laying  mash  should  replace  the  chick  or 
growing  mash  at  three  months  of  age.  The  chick  mash  is  a  high- 
protein  feed  designed  to  produce  strong,  rapid  growth.  After  three 
months  of  age,  however,  a  mash  of  lower  protein  content,  such  as  a 
laying  mash,  is  better  suited  to  the  development  of  vigorous,  go-od- 
sized  pullets.  The  hoppers  of  laying  mash  should  be  closed  two  hours 
before  the  evening  feeding  of  grain  and  opened  at  the  morning  feeding 
of  grain.4 


/  mesh    netting 


Fig.  12. — Green  feed  hopper  for  chickens  over  three  weeks  old. 

Green  Feed. — Fresh,  tender  green  feed  such  as  lettuce,  chard, 
clover  lawn  clippings,  rape,  kale,  beet  tops,  young  green  barley,  young 
alfalfa  and  Sudan  grass  should  be  fed  plentifully  to  growing  chicks 
after  they  are  a  few  days  old.  Materials  like  Sudan  grass  and  alfalfa 
will  be  eaten  better  by  the  chicks  if  cut  very  fine  with  a  cutter.  It  is 
much  more  beneficial  to  chickens  of  any  age  to  allow  them  to  range 
over  areas  of  growing  green  crops  than  it  is  to  feed  them  cut  green 
stuff.  But  if  greens  must  be  cut  and  fed  by  hand,  the  use  of  a  green 
feed  hopper  (fig.  12),  in  which  to  feed  such  finely  cut  green  stuff  as 
alfalfa  will  greatly  lessen  waste.  Such  a  hopper  holds  the  fresh 
material  together  so  that  it  remains  succulent  and  unwilted  for  a 
much  longer  time  than  it  would  if  it  were  fed  on  the  ground  and 
scattered  about  by  the  chickens. 

Enough  green  stuff  should  be  put  in  the  rack  after  the  morning 
feeding  of  grain  to  last  till  noon,  and  only  as  much  more  added  at 


4  For  a  more  detailed  discussion  of  feeding,  the  reader  is  referred  to  Circular 
No.  242,  California  Agricultural  Experiment  Station,  entitled  ' '  Poultry  Feeding. ' ' 


26  UNIVERSITY    OF    CALIFORNIA — EXPERIMENT    STATION 

noon  as  will  be  cleaned  up  before  night.  Leafy  green  feeds,  like 
lettuce  and  kale,  can  be  thrown  to  the  chicks  without  cutting.  They 
will  get  considerable  exercise  in  pulling  the  leaves  to  pieces. 

CROWDING 

Crowding  is  a  prevalent  cause  of  high  mortality  in  chicks.  Fre- 
quently more  chicks  are  put  in  a  brooder  pen  than  it  will  satisfac- 
torily accommodate  at  the  start  and  then  no  provision  is  made  to 
relieve  this  congestion  at  the  earliest  possible  moment.  It  is  appar- 
ently overlooked,  or,  perhaps,  not  fully  realized,  that  a  Leghorn  chick 
will  double  its  weight  in  three  weeks  and  triple  it  in  five  weeks.  With 
so  rapid  an  increase  in  size,  a  pen  of  even  normal  dimensions  for  a 
certain  number  of  day-old  chicks  is  quickly  outgrown.  In  a  pen  over- 
crowded to  start  with,  the  congestion  is  quickly  intensified  and  a 
heavy  mortality  results.  One-half  square  foot  of  floor  space  per  chick 
should  be  allowed  in  the  brooder  room  and  seven  square  inches  per 
chick  under  the  hover. 

The  very  detrimental  effect  of  crowding  on  growing  chicks  should 
not  be  overlooked  by  the  poultry  keeper  and  provision  should  be  made 
to  give  the  chicks  more  room  as  they  increase  in  size.  Ample  room 
will  pay  in  lessened  mortality,  less  cull  stock,  and  more  rapid  growth ; 
cockerels  will  reach  broiler  weight  more  quickly  and  pullets  will  attain 
normal  growth  and  lay  at  an  earlier  age.  In  this  connection  the 
reader's  attention  is  called  to  the  discussion  of  yarding  on  page  16. 

SEPARATION  OF  SEXES 

One  way  to  give  growing  chicks  more  room  to  develop  is  to  separate 
the  cockerels  and  the  pullets  just  as  soon  as  the  sexes  can  be  dis- 
tinguished. In  the  case  of  such  breeds  as  the  Leghorn,  this  can  usually 
be  done  at  about  four  weeks  of  age;  with  the  heavier  breeds  it  is 
often  very  difficult  to  identify  the  sexes  until  the  birds  are  half  grown. 

The  cockerels,  of  the  light  breeds,  particularly,  begin  very  early 
to  demonstrate  their  greater  strength  by  crowding  the  pullets  away 
from  the  feed  troughs,  picking  at  them,  and  otherwise  annoying  them. 
The  early  separation  of  the  sexes  will  allow  the  pullets  to  develop  much 
more  rapidly,  and  the  cockerels  can  be  fed  and  cared  for  to  better 
advantage  in  developing  them  for  market  or  breeding  purposes. 

CHICKS  PILING  UP 
Brooder  chicks  that  have  not  yet  learned  to  roost  always  crowd 
together  when  they  become  chilly.     It  is  instinctive  for  them  to  try 
to  get  underneath  something  warm,  as  they  would  under  the  mother 


Circular  271] 


BROODING    CHICKS    ARTIFICIALLY 


27 


hen,  and  so  they  attempt  to  get  under  each  other  as  they  crowd 
together.  The  strongest  chicks  are  able  to  push  the  weakest  aside  and 
to  work  their  way  to  the  bottom  of  the  huddled  group.  Here  they  are 
soon  smothered  to  death  and  flattened  out  by  the  compact  mass  of 
chicks  on  top  of  them.  The  larger  and  more  numerous  the  chicks 
in  any  given  lot,  the  more  serious  are  the  results  from  crowding  and 
piling. 


Fig.  13. — Roosts  permanently  installed  in  brooder  pen  so  that  chicks  may 
learn  to  roost  naturally  without  the  use  of  " forcing' '  methods. 

Piling  may  result  from  (1)  the  hover  temperature  dropping  at 
night,  (2)  a  rapid  loss  of  vitality  from  coccidiosis,  (3)  keeping  the 
hovers  and  pens  so  hot  that  the  chicks,  being  accustomed  to  high  tem- 
peratures (hot  house  chicks)  are  quickly  chilled  by  sudden  changes 
in  the  weather  or  accidents  to  the  brooding  system,  and  (4)  trans- 
ferring the  chicks  from  warm  to  cold  brooders  in  too  large  lots  before 
thev  have  learned  to  roost  well. 


TEACHING  CHICKS  TO  ROOST 

It  is  very  desirable  to  have  chicks  learn  to  roost  at  an  early  age. 
The  roosts  (1)  keep  the  chicks  separated  and  prevent  their  bunching 
together  as  they  do  after  two  weeks  of  age  when  sleeping  on  the  floor 
of  the  brooder  pen,  (2)  raise  the  chicks  above  the  floor  so  that  the 
air  can  circulate  freely  under  and  around  them,   (3)   supply  better 


28  UNIVERSITY    OF    CALIFORNIA EXPERIMENT    STATION 

ventilation,  and  (4)  eliminate  the  danger  of  chicks  piling  up,  for 
they  cannot  pile  up  when  roosting  without  falling  off.  The  more 
quickly  chicks  are  accustomed  to  do  without  artificial  heat,  the 
stronger  will  be  their  growth  and  the  sooner  they  will  learn  to  roost. 

Perhaps  the  most  satisfactory  way  to  induce  chicks  to  roost  is  to 
place  roosts  in  the  brooder  room  and  let  them  learn  to  roost  naturally. 
Applications  of  this  method  are  illustrated  in  figures  2  and  13. 

When  young  stock  are  rather  slow  in  learning  to  roost  and  it 
becomes  necessary  to  move  them  out  of  the  brooder  house,  they  can  be 
safely  transferred  to  a  number  of  growing  houses  in  lots  of  twenty- 
five.  Twenty -five  is  too  small  a  number  to  cause  any  loss  from  piling 
up,  and  removing  slow  roosting  chicks  to  strange  quarters  is  one  of 
the  quickest  ways  to  induce  them  to  roost. 

The  first  twenty-five  chicks  put  in  each  pen  are  kept  confined  until 
they  are  all  accustomed  to  their  new  quarters  and  to  roosting.  This 
will  take  two  or  three  days.  Then  twenty-five  more  can  be  added  to 
each  pen.  The  first  ones  quickly  teach  the  newcomers  to  roost,  so  that 
twenty-five  more  may  be  added  every  two  or  three  days  until  the  full 
quota  has  been  put  in  each  pen.  The  safest  guide  in  adding  each  lot 
of  twenty-five  is  not  to  add  more  until  those  previously  put  in  are 
roosting  nicely. 

If  the  roosts  are  on  a  droppings  board  and  not  near  the  floor,  a 
wire  covered  panel  should  be  placed  vertically  from  floor  to  front 
edge  of  droppings  board  to  keep  chicks  from  going  underneath.  An 
inclined  portable  runway,  one  foot  wide  and  with  cross  cleats  four 
inches  apart,  should  also  extend  from  the  floor  to  the  droppings  board 
to  enable  the  birds  to  get  up  on  the  roosts  without  difficulty.  These 
devices  will  greatly  facilitate  teaching  the  chicks  to  roost. 

Another  method  sometimes  used  is  known  as  "forced  roosting." 
The  droppings  board  of  a  laying  house  is  prepared  by  stretching  one-  or 
two-inch  mesh  wire  netting  on  the  under  sides  of  the  roosts  and  placing 
a  light  panel  covered  with  this  netting  in  front  of  the  roosts  so  as  to 
fill  the  opening  from  droppings  board  to  ceiling.  This  front  panel 
should  have  a  netting-covered  door  in  it  through  which  the  chicks  and 
troughs  of  feed  can  be  put  into  the  enclosure.  When  completed  a  tight 
coop  with  wire  netting  bottom  and  front  is  formed. 

As  soon  as  the  chicks  have  learned  to  do  without  artificial  heat 
and  are  large  enough  to  roost,  they  are  taken  from  the  brooder  room 
and  put  into  the  previously  prepared  enclosures  described  in  the  pre- 
ceding paragraph.  Since  wire  netting  is  stretched  tightly  under  the 
roosts,  the  chicks  must  either  perch  on  the  roosts  or  on  the  wire  netting 
stretched  tightly  between  them.     Should  they   crowd  together  and 


Circular  271]  brooding  chicks  artificially  29 

attempt  to  pile  up,  the  roosts  and  wire  interfere  with  their  getting 
together  and  resting  comfortably.  The  circulation  of  air  through  the 
wire  from  below  also  keeps  the  bottom  of  the  attempted  "pile  up" 
of  chicks  as  cool  as  the  top  and  the  bottom  chicks  get  just  as  much 
fresh  air  as  any  of  the  others.  Crowding  and  piling  up  are  there- 
fore quickly  discouraged  and  the  chicks  soon  learn  that  the  roosts 
are  much  more  comfortable  than  wire  netting  to  roost  on. 

Forced  roosting  should  not  be  attempted  with  chicks  under  six 
weeks  of  age  or  with  lots  of  more  than  200  in  any  one  enclosure.  It 
is  also  best  to  separate  the  sexes  when  using  this  method,  since 
cockerels  and  pullets  learn  to  roost  more  readily  when  placed  in 
separate  coops. 

The  authors  wish  to  acknowledge  their  indebtedness  to  Professor 
W.  E.  Lloyd  of  the  Division  of  Poultry  Husbandry  for  the  experi- 
mental data  on  which  Table  1  is  based ;  to  Mr.  R.  B.  Easson,  Extension 
Poultry  Specialist,  who  was  instrumental  in  making  the  field  survey 
from  which  was  obtained  other  fuel  costs  of  brooding  given  in  the 
test ;  and  to  Mr.  J.  D.  Long  of  the  Division  of  Agricultural  Engineer- 
ing for  his  help  in  lettering  the  drawings. 

Blueprint  plans  for  the  houses  illustrated  in  figures  1,  5,  and  8  of  this 
bulletin  may  be  obtained  on  loan  from  the  Division  of  Agricultural  Extension. 
College  of  Agriculture,  Berkeley,  California. 


STATION  PUBLICATIONS  AVAILABLE  FOB  FREE  DISTRIBUTION 


No. 

253. 

261. 

262. 

263. 
268. 
270. 

273. 

275. 

276. 
277. 
278. 
279. 
280. 

283. 
285. 
286. 
287. 
294. 
298. 
804. 

308. 


312. 
317. 

319. 
321. 
324. 

325. 


328. 
331. 
334. 


BULLETINS 

No. 

Irrigation   and   Soil   Conditions  in  the  335. 

Sierra  Nevada  Foothills,  California. 

Mel  ax  u  ma    of    the    Walnut,     "Juglans  336. 

regia." 

Citrus   Diseases   of   Florida   and   Cuba  339. 

Compared  with  those  of  California. 

Size  Grades  for  Ripe  Olives.  341. 

Growing  and  Grafting  Olive  Seedlings.  343. 

A  Comparison  of  Annual  Cropping,  Bi-  344. 

ennial  Cropping  and  Green  Manures 
on  the  Yield  of  Wheat.  347. 

Preliminary  Report  on  Kearney  Vine- 
yard Experimental  Drain.  348. 

The  Cultivation  of  Belladonna  in  Cali-  349. 

fornia. 

The   Pomegranate.  350. 

Sudan  Grass.  351. 

Grain   Sorghums.  352. 

Irrigation  of  Rice  in  California. 

Irrigation  of  Alfalfa  in  the  Sacramento  353. 

Valley.  354. 

The  Olive  Insects  of  California.  355. 

The  Milk  Goat  in  California.  357. 

Commercial   Fertilizers. 

Vinegar  from  Waste  Fruits. 

Bean    Culture  in   California.  358. 

Seedless  Raisin  Grapes. 

A  Study  of  the  Effects  of  Freezes  on  359. 

Citrus   in   California.  360. 

I.  Fumigation  with  Liquid  Hydrocyanic 
Acid.  II.  Physical  and  Chemical  Prop-  361. 

erties  of  Liquid  Hydrocyanic  Acid. 

Mariout  Barley.  362. 

Selections  of   Stocks  in  Citrus   Propa-  363. 

gation. 

Caprifigs  and  Caprification.  364. 

Commercial  Production  of  Grape  Syrup. 

Storage  of  Perishable  Fruit  at  Freezing  365. 

Temperatures.  366. 

Rice  Irrigation  Measurements  and  Ex- 
periments    in     Sacramento     Valley,  368 
1914-1919. 

Prune  Growing  in  California.  369. 

Phylloxera-Resistant  Stocks. 

Preliminary  Volume  Tables  for  Second- 
Growth  Redwood. 


Cocoanut  Meal  as  a  Feed  for  Dairy 
Cows  and  Other  Livestock. 

The  Preparation  of  Nicotine  Dust  as 
an  Insecticide. 

The  Relative  Cost  of  Making  Logs  from 
Small    and    Large   Timber. 

Studies  on  Irrigation  of  Citrus  Groves. 

Cheese  Pests  and  Their  Control. 

Cold  Storage  as  an  Aid  to  the  Market 
ing  of  Plums. 

The  Control  of  Red  Spiders  in  Decidu- 
ous Orchards. 

Pruning  Young  Olive  Trees. 

A  Study  of  Sidedraft  and  Tractor 
Hitches. 

Agriculture  in  Cut-over  Redwood  Lands. 

California  State  Dairy  Cow  Competition. 

Further  Experiments  in  Plum  Pollina- 
tion. 

Bovine  Infectious  Abortion. 

Results  of  Rice  Experiments  in   1922. 

The  Peach  Twig  Borer. 

A  Self-mixing  Dusting  Machine  for 
Applying  Dry  Insecticides  and 
Fungicides. 

Black  Measles,  Water  Berries,  and 
Related   Vine   Troubles. 

Fruit  Beverage  Investigations. 

Gum  Diseases  of  Citrus  Trees  in  Cali- 
fornia. 

Preliminary  Yield  Tables  for  Second 
Growth  Redwood. 

Dust  and  the  Tractor  Engine. 

The  Pruning  of  Citrus  Trees  in  Cali- 
fornia. 

Fungicidal  Dusts  for  the  Control  of 
Bunt. 

Avocado  Culture  in  California. 

Turkish  Tobacco  Culture,  Curing  and 
Marketing. 

Bacterial  Decomposition  of  Olives  dur- 
ing Pickling. 

Comparison  of  Woods  for  Butter  Boxes 


CIRCULARS 

No.  No. 

70.  Observations   on    the    Status   of    Corn  161. 
Growing  in  California.  164. 
87.  Alfalfa.  165. 
111.  The  Use  of  Lime  and  Gypsum  on  Cali- 
fornia Soils.  166. 
113.  Correspondence  Courses  in  Agriculture.  167. 
117.  The    Selection    and    Cost    of    a    Small  170. 

Pumping  Plant. 

136.  Melilotua   mdica    as    a    Green-Manure  172. 

Crop  for  California.  173. 
127.  House  Fumigation. 

129.  The  Control  of  Citrus  Insects.  174. 

144.   Qidium  or  Powdery  Mildew  of  the  Vine.  175. 

151.  Feeding  and  Management  of  Hogs. 

152.  Some    Observations  on  the  Bulk    Hand-  178. 

ling  of  Grain  in   California.  179. 

153.  Announcement  of  the  California  State 

Dairy  Cow  Competition,   1916-18.  182. 

154.  Irrigation  Practice  in  Growing  Small 

Fruit  in  California.  184. 

155.  Bovine  Tuberculosis.  188. 
157.  Control  of  the  Pear  Scab.  190. 

159.  Agriculture  in  the  Imperial  Valley.  193. 

160.  Lettuce  Growing  in  California.  198. 


Potatoes  in  California. 

Small  Fruit  Culture  in  California. 

Fundamentals   of    Sugar   Beet   Culture 

under  California  Conditions. 
The  County  Farm  Bureau. 
Feeding  Stuffs  of  Minor  Importance. 
Fertilizing  California  Soils  for  the  1918 

Crop. 
Wheat  Culture. 
The    Construction    of    the    Wood-Hoop 

Silo. 
Farm   Drainage  Methods. 
Progress  Report  on  the  Marketing  and 

Distribution  of  Milk. 
The  Packing  of  Apples  in  California. 
Factors    of    Importance    in    Producing 

Milk  of  Low  Bacterial  Count. 
Extending  the  Area  of  Irrigated  Wheat 

in   California  for  1918. 
A  Flock  of  Sheep  on  the  Farm. 
Lambing  Sheds. 

Agriculture  Clubs  in  California. 
A  Study  of  Farm  Labor  in  California. 
Syrup  from  Sweet  Sorghum. 


CIRCULARS — Continued 


No. 
199. 

201. 
202. 

203. 
205. 
206. 
208. 

209. 
210. 
212. 
214. 

215. 
217. 

218. 

219. 
224. 


228. 
230. 

232. 

233. 
234. 

235. 

236. 

237. 

238. 
239. 

240. 


Onion  Growing  in  California. 

Helpful  Hints  to  Hog  Raisers. 

County  Organizations  for  Rural  Fire 
Control. 

Peat  as  a  Manure  Substitute. 

Blackleg. 

Jack  Cheese. 

Summary  of  the  Annual  Reports  of  the 
Farm  Advisors  of  California. 

The  Function  of  the  Farm  Bureau. 

Suggestions  to  the  Settler  in  California. 

Salvaging  Rain-Damaged  Prunes. 

Seed  Treatment  for  the  Prevention  of 
Cereal  Smuts. 

Feeding  Dairy  Cows  in  California. 

Methods  for  Marketing  Vegetables  in 
California. 

Advanced  Registry  Testing  of  Dairy 
Cows. 

The  Present  Status  of  Alkali. 

Control  of  the  Brown  Apricot  Scale 
and  the  Italian  Pear  Scale  on  Decid- 
uous Fruit  Trees. 

Vineyard  Irrigation  in  Arid  Climates. 

Testing  Milk,  Cream,  and  Skim  Milk 
for  Butterfat. 

Harvesting  and  Handling  California 
Cherries  for  Eastern  Shipment. 

Artificial  Incubation. 

Winter  Injury  to  Young  Walnut  Trees 
during  1921-22. 

Soil  Analysis  and  Soil  and  Plant  Inter- 
relations. 

The  Common  Hawks  and  Owls  of  Cali- 
fornia from  the  Standpoint  of  the 
Rancher. 

Directions  for  the  Tanning  and  Dress- 
ing of  Furs. 

The  Apricot  in  California. 

Harvesting  and  Handling  Apricots  and 
Plums  for  Eastern   Shipment. 

Harvesting  and  Handling  Pears  for 
Eastern  Shipment. 


No. 
241. 

242. 
243. 

244. 
245. 
247. 
248. 

249. 
250. 

251. 


252. 
253. 
254. 

255. 

256. 
257. 
258. 
259. 
260. 

261. 
262. 
263. 
264. 

265. 
266. 


Harvesting  and  Handling  Peaches  for 
Eastern  Shipment. 

Poultry  Feeding. 

Marmalade  Juice  and  Jelly  Juice  from 
Citrus  Fruits. 

Central  Wire  Bracing  for  Fruit  Trees. 

Vine  Pruning  Systems. 

Colonization  and  Rural  Development. 

Some  Common  Errors  in  Vine  Prunimg 
and  Their  Remedies. 

Replacing  Missing  Vines. 

Measurement  of  Irrigation  Water  on 
the   Farm. 

Recommendations  Concerning  the  Com- 
mon Diseases  and  Parasites  of 
Poultry   in    California. 

Supports  for  Vines. 

Vineyard   Plans. 

The  Use  of  Artificial  Light  to  Increase 
Winter  Egg  Production. 

Leguminous  Plants  as  Organic  Fertil- 
izer in  California  Agriculture. 

The  Control  of  Wild  Morning  Glory. 

The  Small-Seeded  Horse  Bean. 

Thinning  Deciduous  Fruits. 

Pear  By-prodncts. 

A  Selected  List  of  References  Relating 
to  Irrigation  in  California. 

Sewing  Grain  Sacks. 

Cabbage  Growing  in  California. 

Tomato  Production  in  California. 

Preliminary  Essentials  to  Bovine  Tuber- 
culosis Control. 

Plant  Disease  and  Pest  Control. 

Analyzing  the  Citrus  Orchard  by  Means 
of  Simple  Tree  Records. 

The  Tendency  of  Tractors  to  Rise  in 
Front;  Causes  and  Remedies. 


